Tomoyuki Otsuka

Usefulness of High Suction Pressure for Sufficient Tissue Collection During Endobronchial Ultrasound Guided Transbronchial Needle Aspiration

Introduction The optimal suction pressure during endobronchial ultrasound guided transbronchial needle aspiration (EBUS-TBNA) remains to be determined. The aim of this study was to compare suction pressures for performance in collecting sufficient tissue specimens from mediastinal and hilar lymph nodes during EBUS-TBNA. Methods Retrospective analysis of consecutive patients with mediastinal and hilar lymphadenopathy who underwent EBUS-TBNA over a 3-year period. Results from patients who underwent EBUS-TBNA using a dedicated 20-mL VacLoc (Merit Medical Systems, Inc, South Jordan, UT) syringe (conventional method, group C) were compared with results from patients in whom a disposable 30-mL syringe (high pressure group, group H) was used. The yield for sufficient histologic specimen retrieval and amount of tissue obtained were compared between the 2 groups. Results Of 178 patients who underwent EBUS-TBNA, 131 had lung cancer confirmed by EBUS-TBNA: 35 in group C and 96 in group H. There were 7 patients in group C and 6 in group H who received final diagnoses by cytology alone. There were 28 in group C and 90 in group H who were diagnosed by both cytology and histology. There was a statistically significant difference between the groups in terms of the rate of sufficient sampling for histological specimens (p = 0.04). The H group revealed a tissue area approximately twice that of the C group (p = 0.003). There were no major procedure-related complications in either group. Conclusion Higher suction pressures with larger syringe volumes during EBUS-TBNA may be useful for safely collecting sufficient tissue specimens.

Rapid intracranial response to osimertinib, without radiotherapy, in nonsmall cell lung cancer patients harboring the EGFR T790M mutation: Two Case Reports

Rationale: Most of nonsmall cell lung cancer (NSCLC) patients harboring epidermal growth factor receptor (EGFR) activating mutations eventually acquire resistance to the first EGFR-tyrosine kinase inhibitors (TKIs) therapy after varying periods of treatment. Of note, approximately one-third of those patients develop brain metastases, which deteriorate their quality of life and survival. The effect of systemic chemotherapy on brain metastases after acquisition of EGFR-TKI resistance is limited, and thus far, whole-brain radiation therapy, which may cause the harmful effect on neurocognitive functions, has been the only established therapeutic option for especially symptomatic brain metastases. Osimertinib is a third-generation oral, potent, and irreversible EGFR-TKI. It can bind to EGFRs with high affinity even when the EGFR T790M mutation exists in addition to the sensitizing mutations. Its clinical efficacy for NSCLC patients harboring the T790M mutation has already been shown; however, the evidence of osimertinib on brain metastases has not been documented well, especially in terms of the appropriate timing for treatment and its response evaluation. Patient concerns, Diagnoses, and Interventions: We experienced 2 NSCLC patients with the EGFR T790M mutation; a 67-year-old woman with symptomatic multiple brain metastases administered osimertinib as seventh-line chemotherapy, and a 76-year old man with an asymptomatic single brain metastasis administered osimertinib as fifth-line chemotherapy. Outcomes: These patients showed great response to osimertinib within 2 weeks without radiation therapy. Lessons: These are the first reports to reveal the rapid response of the brain metastases to osimertinib within 2 weeks. These cases suggest the possibility that preemptive administration of osimertinib may help patients to postpone or avoid radiation exposures. In addition, rapid reassessment of the effect of osimertinib on brain metastases could prevent patients from being too late to receive essential radiotherapy.

Randomized Phase II trial of paclitaxel and carboplatin followed by gemcitabine switch- maintenance therapy versus gemcitabine and carboplatin followed by gemcitabine continuation-maintenance therapy in previously untreated advanced non-small cell lung cancer

BackgroundIn recent years, maintenance chemotherapy is increasingly being recognized as a new treatment strategy to improve the outcome of advanced non-small cell lung cancer (NSCLC). However, the optimal maintenance strategy is still controversial. Gemcitabine is a promising candidate for single-agent maintenance therapy because of little toxicity and good tolerability. We have conducted a randomized phase II study to evaluate the validity of single-agent maintenance chemotherapy of gemcitabine and to compare continuation- and switch-maintenance.MethodsChemonaïve patients with stage IIIB/IV NSCLC were randomly assigned 1:1 to either arm A or B. Patients received paclitaxel (200 mg/m2, day 1) plus carboplatin (AUC 6 mg/mL/min, day 1) every 3 weeks in arm A, or gemcitabine (1000 mg/m2, days 1 and 8) plus carboplatin (AUC 5 mg/mL/min, day1) every 3 weeks in arm B. Non-progressive patients following 3 cycles of induction chemotherapy received maintenance gemcitabine (1000 mg/m2, days 1 and 8) every 3 weeks. (Trial registration: UMIN000008252)ResultsThe study was stopped because of delayed accrual at interim analysis. Of the randomly assigned 50 patients, 49 except for one in arm B were evaluable. Median progression-free survival (PFS) was 4.6 months for arm A vs. 3.5 months for arm B (HR = 1.03; 95% CI, 0.45–2.27; p = 0.95) and median overall survival (OS) was 15.0 months for arm A vs. 14.8 months for arm B (HR = 0.79; 95% CI, 0.40–1.51; p = 0.60), showing no difference between the two arms. The response rate, disease control rate, and the transit rate to maintenance phase were 36.0% (9/25), 64.0% (16/25), and 48% (12/25) for arm A vs. 16.7% (4/24), 50.0% (12/24), and 33% (8/24) for arm B, which were also statistically similar between the two arms (p = 0.13, p = 0.32, and p = 0.30, respectively). Both induction regimens were tolerable, except that more patients experienced peripheral neuropathy in arm A. Toxicities during the maintenance phase were also minimal.ConclusionSurvival and overall response were not significantly different between the two arms. Gemcitabine may be well-tolerable and feasible for maintenance therapy.

Favorable response to trastuzumab plus irinotecan combination therapy in two patients with HER2-positive relapsed small-cell lung cancer

Small-cell lung cancer (SCLC) easily recurs with multidrug resistance phenotype. However, standard therapeutic strategies for relapsed-SCLC remain unestablished. Human epidermal growth factor receptor 2 (HER2) expression correlates with poor prognosis in extensive disease-SCLC. We have reported previously that HER2 expression is upregulated when HER2-positive SCLC cells acquire chemoresistance, and also demonstrated that trastuzumab exerts significant antitumor activity toward HER2-upregulated chemoresistant SCLC, mainly via antibody-dependent cell-mediated cytotoxicity mechanism. Based on these preclinical data, we treated two patients with HER2-positive SCLC by combination of trastuzumab (6 mg/kg, day 1) and irinotecan (80 mg/m(2), days 1 and 8) every 21 days as the third-line chemotherapy following two prior regimens, first-line carboplatin plus etoposide and second-line amrubicin. One patient achieved partial response after the first cycle and received 6 cycles in total without disease progression for 4.5 months. The other also received 4 cycles and kept stable disease for 3.5 months. This treatment can be continued safely at an outpatient clinic without any severe adverse event. In conclusion, trastuzumab plus irinotecan chemotherapy is promising and feasible against HER2-positive relapsed SCLC. Further clinical studies are encouraged to confirm the antitumor efficacy of trastuzumab in SCLC.

Clinical implications of monitoring nivolumab immunokinetics in non–small cell lung cancer patients

BACKGROUND. The PD-1–blocking antibody nivolumab persists in patients several weeks after the last infusion. However, no study has systematically evaluated the maximum duration that the antibody persists on T cells or the association between this duration and residual therapeutic efficacy or potential adverse events. METHODS. To define the duration of binding and residual efficacy of nivolumab after discontinuation, we developed a simplified strategy for T cell monitoring and used it to analyze T cells from peripheral blood from 11 non–small cell lung cancer patients previously treated with nivolumab. To determine the suitability of our method for other applications, we compared transcriptome profiles between nivolumab-bound and nivolumab-unbound CD8 T cells. We also applied T cell monitoring in 2 nivolumab-treated patients who developed progressive lung tumors during long-term follow-up. RESULTS. Prolonged nivolumab binding was detected more than 20 weeks after the last infusion, regardless of the total number of nivolumab infusions (2–15 doses) or type of subsequent treatment, in 9 of the 11 cases in which long-term monitoring was possible. Ki-67 positivity, a proliferation marker, in T cells decreased in patients with progressive disease. Transcriptome profiling identified the signals regulating activation of nivolumab-bound T cells, which may contribute to nivolumab resistance. In 2 patients who restarted nivolumab, T cell proliferation markers exhibited the opposite trend and correlated with clinical response. CONCLUSIONS. Although only a few samples were analyzed, our strategy of monitoring both nivolumab binding and Ki-67 in T cells might help determine residual efficacy under various types of concurrent or subsequent treatment. TRIAL REGISTRATION. University Hospital Medical Information Network Clinical Trials Registry, UMIN000024623. FUNDING. This work was supported by Japan Society for the Promotion of Science KAKENHI (JP17K16045, JP18H05282, and JP15K09220), Japan Agency for Medical Research and Development (JP17cm0106310, JP18cm0106335 and JP18cm059042), and Core Research for Evolutional Science and Technology (JPMJCR16G2).

Classification of idiopathic interstitial pneumonias using anti–myxovirus resistance-protein 1 autoantibody

Chronic fibrosing idiopathic interstitial pneumonia (IIP) can be divided into two main types: idiopathic pulmonary fibrosis (IPF), a steroid-resistant and progressive disease with a median survival of 2–3 years, and idiopathic non-specific interstitial pneumonia (INSIP), a steroid-sensitive and non-progressive autoimmune disease. Although the clinical courses of these two diseases differ, they may be difficult to distinguish at diagnosis. We performed a comprehensive analysis of serum autoantibodies from patients definitively diagnosed with IPF, INSIP, autoimmune pulmonary alveolar proteinosis, and sarcoidosis. We identified disease-specific autoantibodies and enriched KEGG pathways unique to each disease, and demonstrated that IPF and INSIP are serologically distinct. Furthermore, we discovered a new INSIP-specific autoantibody, anti–myxovirus resistance-1 (MX1) autoantibody. Patients positive for anti-MX1 autoantibody constituted 17.5% of all cases of chronic fibrosing IIPs. Notably, patients rarely simultaneously carried the anti-MX1 autoantibody and the anti–aminoacyl-transfer RNA synthetase autoantibody, which is common in chronic fibrosing IIPs. Because MX1 is one of the most important interferon-inducible anti-viral genes, we have not only identified a new diagnostic autoantibody of INSIP but also obtained new insight into the pathology of INSIP, which may be associated with viral infection and autoimmunity.